CHAP. IV.] NAILING SECURELY AND SAFELY. 511 



the first being of the size of the nail shank, the 

 second is to receive a small part of the head. This 

 mode is, of course, best adapted to the " improved 

 shoe" recommended at page 497, where a shoulder 

 and groove supply the place of fullering. But, in 

 every form of shoe, and every modification of nail- 

 ing, the manifest advantage of admitting the nail- 

 head to a rest or protection from rude concussions 

 against the ground, must be evident, when the 

 counter- sink part of the head is allowed to lie deep 

 in the shoe. 



The number of nail holes has hitherto been 

 eight, but a better practice prevails in some forges 

 of driving seven nails only, three on the inside, 

 four outside ; whereby the fourth nail outside is 

 thrown so much farther back than the third nail 

 inside. More play is thus allowed for expansion 

 at the quarters ; and if the punching and driving 

 be performed effectively, the hold thus obtained 

 will be found fully adequate to any service to 

 which the greater number of nails is applied. 

 The safety of the shoe depends more upon the 

 nails' passing through good sound horn, and filling 

 up the punch-holes in the shoe, than upon their 

 number. A good workman can hear when the nails 

 thus telly by the sound of driving. After punching, 

 the smith must not apply heat, or a hammer to the 

 shoe, with a view to reduce any bulge, or burr, 

 which the punch may have occasioned ; for this ex- 

 ploded practice spoils the shape and size of the 

 holes, upon the fitness whereof wholly depends the 



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